Methods of detecting power of individual carrier of aggregated carrier

ABSTRACT

Aspects of this disclosure relate to detecting power associated with an individual carrier of a carrier aggregated signal. In an embodiment, an aggregated carrier including at least a first carrier and a second carrier is provided. An indication of power of the first carrier of the aggregated carrier is detected. Separately from detecting the indication of power of the first carrier, an indication of power of the second carrier of the aggregated carrier is detected. The power associated with a radio frequency (RF) signal provided to an RF source associated with the first carrier can be adjusted based on the indication of power of the first carrier.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.16/148,858, filed Oct. 1, 2018 and titled “METHODS OF DETECTING POWER OFINDIVIDUAL CARRIER OF AGGREGATED CARRIER,” which is divisional of U.S.patent application Ser. No. 15/190,032, filed Jun. 22, 2016 and titled“DETECTING POWER OF INDIVIDUAL CARRIER OF AGGREGATED CARRIER,” whichclaims the benefit of priority under 35 U.S.C. § 119(e) of U.S.Provisional Patent Application No. 62/185,507, filed Jun. 26, 2015 andtitled “POWER DETECTION OF INDIVIDUAL CARRIER OF AGGREGATED CARRIER,”the disclosures of each of which are hereby incorporated by reference intheir entireties herein. This application is also related to U.S. patentapplication Ser. No. 15/190,075, filed on Jun. 22, 2016 and titled“POWER DETECTION OF INDIVIDUAL CARRIER OF AGGREGATED CARRIER,” thedisclosure of which is hereby incorporated by reference in its entiretyherein.

BACKGROUND Technical Field

This disclosure relates to electronic systems and, in particular, toradio frequency (RF) circuits.

Description of the Related Technology

Some systems in an uplink channel for Long Term Evolution (LTE) use asingle uplink carrier. The uplink channel can be from a handset to abase station. A carrier can be a signal that is modulated with an inputsignal to transmit information. The carrier is typically at asignificantly higher frequency than the input signal. The carrier can bea radio frequency signal. In LTE systems with a single uplink carrier,power control is typically maintained through the use of one or moredirectional couplers and one or more associated power detectors. In suchsystems, there is typically no need to control power of multipletransmissions.

In Advanced-LTE, carrier aggregation can increase bandwidth andconsequently increase data transmission rates. Carrier aggregation cancombine carriers at a device to increase user data rates across a cellcoverage area. Carrier aggregation can provide relatively high peak datarates, increased data rates for all users in a cell, and higher capacityfor bursty applications. Specified limits to total carrier power inAdvanced-LTE carrier aggregation systems can be difficult to meet.

SUMMARY OF CERTAIN INVENTIVE ASPECTS

The innovations described in the claims each have several aspects, nosingle one of which is solely responsible for its desirable attributes.Without limiting the scope of the claims, some prominent features ofthis disclosure will now be briefly described.

An aspect of this disclosure is a carrier aggregation system thatincludes RF sources, such as power amplifiers, each associated with aseparate carrier. The system includes a transmission output configuredto provide a carrier aggregated signal. For example, the transmissionoutput can be an output configured to provide the carrier aggregatedsignal to an antenna, such as a transmission output of a frequencymultiplexing circuit (e.g., a diplexer or a triplexer). The carrieraggregated signal includes an aggregation of the separate carriersassociated with the RF sources. The apparatus also includes adirectional coupler configured to provide an indication of RF power ofone of the separate carriers.

The carrier aggregated signal can be in accordance with an Advanced LongTerm Evolution standard. The carrier aggregated signal can be aninter-band carrier aggregated signal. Alternatively or additionally, thecarrier aggregated signal can be an intra-band carrier aggregatedsignal.

The system can include a frequency multiplexing circuit, in which thedirectional coupler is in a signal path between an RF source of the RFsources and the frequency multiplexing circuit. In some otherembodiments, the system can include a frequency multiplexing circuitcoupled between the RF sources and the directional coupler. A diplexeris an example of a frequency multiplexing circuit.

The system can include a band select switch, in which the directionalcoupler is in a signal path between an RF source of the RF sources andthe band select switch. The system can additionally include a band passfilter, in which the band select switch is coupled between thedirectional coupler and the band pass filter.

The system can include a second directional coupler and a frequencymultiplexing circuit. The directional coupler and the second directionalcoupler can be associated with different RF sources of the RF sources.The frequency multiplexing circuit can be coupled between thetransmission output and the directional coupler and coupled between thetransmission output and the second directional coupler.

The system can include a power detector coupled to directional coupler.In some embodiments, the system can include a multi-throw switch coupledbetween the directional coupler and the power detector.

Another aspect of this disclosure is a power amplifier system withcarrier aggregation. The system includes power amplifiers, atransmission output, and a detection output. The power amplifiersinclude at least a first power amplifier associated with a first carrierand a second power amplifier associated with a second carrier. Thetransmission output is configured to provide a carrier aggregated signalthat includes an aggregation of at least the first carrier and thesecond carrier. For example, the transmission output can be an outputconfigured to provide the carrier aggregated signal to an antenna, suchas a transmission output of a frequency multiplexing circuit (e.g., adiplexer or a triplexer). The detection output is configured to providean indication of power of an individual carrier of the aggregatedcarrier. The individual carrier is either the first carrier or thesecond carrier. The detection output can be, for example, an output of adirectional coupler, an output of a power detector, or an output of afrequency multiplexing circuit coupled between a directional coupler andtwo or more power detectors.

The system can be configured for uplink channel communication. In someembodiments, the system can include a band pass filter and a directionalcoupler, in which the directional coupler is in a signal path betweenthe first power amplifier and the band pass filter. According to certainembodiments, the system can include a first directional couplerassociated with the first power amplifier, a second directional couplerassociated with the second power amplifier, and a frequency multiplexingcircuit coupled between the transmission output and the firstdirectional coupler and coupled between the transmission output and thesecond directional coupler. In a number of embodiments, the system caninclude a directional coupler and a frequency multiplexing circuitcoupled between the power amplifiers and the directional coupler.

Another aspect of this disclosure is a carrier aggregation circuitincluding radio frequency (RF) sources including a first RF sourceassociated with a first carrier and a second RF source associated with asecond carrier; a frequency multiplexing circuit configured to provide acarrier aggregated signal, the carrier aggregated signal including anaggregation of the first carrier and the second carrier; and means forproviding an indication of RF power of one of the separate carriers.

Another aspect of this disclosure is a mobile wireless communicationdevice. The device includes an antenna configured to transmit radiofrequency (RF) signals, power amplifiers each associated with a separatecarrier, a frequency multiplexing circuit coupled between the antennaand the power amplifiers, and a directional coupler configured toprovide an indication of RF power of a selected one of the separatecarriers. The frequency multiplexing circuit is configured to provide acarrier aggregated signal to the antenna, in which the carrieraggregated signal including an aggregation of least two of the separatecarriers associated with the power amplifiers.

In certain embodiments, the mobile wireless communication deviceincludes a band select switch, and the directional coupler beingdisposed in a signal path between a power amplifier of the poweramplifiers and the band select switch. According to some embodiments,the mobile wireless communication device includes a band pass filter,and the directional coupler being disposed in a signal path between apower amplifier of the power amplifiers and the band pass filter. In anumber of embodiments, the mobile wireless communication device includesa second directional coupler configured to provide an indication of RFpower of different one of the separate carriers. According to certainembodiments, the directional coupler is coupled between the frequencymultiplexing circuit and the antenna.

Another aspect of this disclosure is a power amplifier module thatincludes power amplifiers each associated with a separate carrier, atransmission node configured to provide a carrier aggregated signal fortransmission, and a directional coupler configured to provide anindication of radio frequency (RF) power of a selected one of theseparate carriers. The carrier aggregated signal includes an aggregationof the separate carriers associated with the power amplifiers.

In some embodiments, the power amplifier module includes a band selectswitch, and the directional coupler being in a signal path between theband select switch and a first power amplifier of the power amplifiers.According to certain embodiments, the power amplifier module includes atransmit/receive switch, and the directional coupler being in a signalpath between the band select switch and a first power amplifier of thepower amplifiers. The power amplifier module can include a powerdetector configured to receive the indication of RF power.

The power amplifier module can include a frequency multiplexing circuitcoupled between the transmission node and each of the power amplifiers.In some of these implementations, the power amplifier module includes aduplexer coupled between the frequency multiplexing circuit and a poweramplifier of the power amplifiers.

Another aspect of this disclosure is a method of detecting powerassociated with individual carriers of a carrier aggregated signal. Themethod includes providing an aggregated carrier; detecting an indicationof power of a first carrier of the aggregated carrier; and separatelyfrom detecting the indication of power of the first carrier, detectingan indication of power of a second carrier of the aggregated carrier.

The method can be performed in a mobile device. The method can furtherinclude adjusting a power associated with a radio frequency (RF) signalprovided to an RF source associated with the first carrier based atleast partly on the indication of power of the first carrier.

In some embodiments, detecting the indication of power of the firstcarrier can be based on an output of a directional coupler coupledbetween a frequency multiplexing circuit and an antenna. According tocertain embodiments, detecting the indication of power of the firstcarrier is based on an output of a first directional coupler anddetecting the indication of power of the second carrier is based on anoutput of a second directional coupler. In such embodiments, the firstdirectional coupler can be coupled between a power amplifier and amulti-throw radio frequency switch. In a number of embodiments,detecting the indication of power of the first carrier and detecting theindication of power of the second carrier are both performed using anoutput of a single directional coupler. For instance, detecting theindication of power of the first carrier can be performed with a firstpower detector and detecting the indication of power of the secondcarrier can be performed with a second power detector. In some suchembodiments, detecting the indication of power of the first carrier anddetecting the indication of power of the second carrier are performednon-concurrently.

Another aspect of this disclosure is an electronically implementedmethod that includes receiving an indication of power of an individualcarrier of an aggregated carrier, the aggregated carrier including anaggregation of the individual carrier and at least another individualcarrier; and adjusting a power associated with a radio frequency (RF)signal provided to an RF source based associated with the individualcarrier at least partly on the indication of power of the individualcarrier. The method can be performed, for example, in a mobile device.

Another aspect of this disclosure is an apparatus that includes afeedback control circuit and an amplifier. The feedback control circuitis configured to receive an indication of power of an individual carrierof an aggregated carrier and to generate a control signal based at leastpartly on the indication of power of the individual carrier. Theamplifier is configured to receive the control signal and to cause apower associated with the individual carrier to be adjusted based atleast partly on the control signal.

The apparatus can include a second amplifier. The feedback controlcircuit can be configured to receive an indication of power of anotherindividual carrier of the aggregated carrier and to generate a secondcontrol signal based at least partly on the indication of power of theanother individual carrier. The second amplifier can be configured toreceive the second control signal. The second amplifier can beconfigured to cause a power associated with the other individual carrierto be adjusted based at least partly on the second control signal.

For purposes of summarizing the disclosure, certain aspects, advantagesand novel features of the innovations have been described herein. It isto be understood that not necessarily all such advantages may beachieved in accordance with any particular embodiment. Thus, theinnovations may be embodied or carried out in a manner that achieves oroptimizes one advantage or group of advantages as taught herein withoutnecessarily achieving other advantages as may be taught or suggestedherein.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of this disclosure will be described, by way of non-limitingexample, with reference to the accompanying drawings.

FIG. 1A is a schematic diagram of an electronic system for detectingpower of individual carriers of a carrier aggregated signal according toan embodiment.

FIG. 1B is a schematic diagram of an example electronic system fordetecting power of individual carriers of a carrier aggregated signalaccording to another embodiment.

FIG. 1C is a schematic diagram of an example electronic system fordetecting power of individual carriers of a carrier aggregated signalaccording to another embodiment.

FIG. 2A is a schematic diagram of an electronic system with uplinkcarrier aggregation and power detection of individual carriers accordingto an embodiment.

FIG. 2B is a schematic diagram of an electronic system with uplinkcarrier aggregation and power detection of individual carriers accordingto another embodiment.

FIG. 2C is a schematic diagram of an electronic system with uplinkcarrier aggregation and power detection of individual carriers accordingto another embodiment.

FIGS. 2D, 2E, 2F, and 2G are schematic diagrams of example electronicmodules according to certain embodiments.

FIG. 3A is a schematic diagram of an electronic system with uplinkcarrier aggregation and power detection of individual carriers accordingto an embodiment.

FIG. 3B is a schematic diagram of an electronic system with uplinkcarrier aggregation and power detection of individual carriers accordingto another embodiment. FIG. 3C is an illustrative diagram of timing oftime division duplexing with non-overlapping transmission and associatedpower consumption in the electronic system of FIG. 3B.

FIG. 4A is a schematic diagram of an electronic system with uplinkcarrier aggregation and power detection of individual carriers accordingto another embodiment. FIG. 4B is an illustrative diagram of timing oftime division duplexing with overlapping transmission and associatedpower consumption in the electronic system of FIG. 4A.

FIG. 5A is a schematic diagram of an electronic system with uplinkcarrier aggregation and power detection of individual carriers accordingto another embodiment.

FIG. 5B is a schematic diagram of an electronic system with carrieraggregation and power detection of individual carriers according toanother embodiment.

FIG. 5C is a schematic diagram of an electronic system with carrieraggregation and power detection of individual carriers according toanother embodiment.

FIG. 6A is a schematic diagram of a closed loop power control systemaccording to an embodiment.

FIG. 6B is a flow diagram of an illustrative process of controllingpower of individual carriers of a carrier aggregated signal according toan embodiment.

FIG. 6C is a schematic diagram of a closed loop power control systemaccording to another embodiment.

FIG. 7 is a schematic block diagram of an example wireless communicationdevice that can include any combination of features of the powerdetection of individual carriers of an aggregated signal discussedherein.

DETAILED DESCRIPTION OF CERTAIN EMBODIMENTS

The following detailed description of certain embodiments presentsvarious descriptions of specific embodiments. However, the innovationsdescribed herein can be embodied in a multitude of different ways, forexample, as defined and covered by the claims. In this description,reference is made to the drawings where like reference numerals and/orsymbols can indicate identical or functionally similar elements. It willbe understood that elements illustrated in the figures are notnecessarily drawn to scale. Moreover, it will be understood that certainembodiments can include more elements than illustrated in a drawingand/or a subset of the elements illustrated in a drawing. Further, someembodiments can incorporate any suitable combination of features fromtwo or more drawings.

As discussed above, in Advanced-LTE, carrier aggregation can increasebandwidth and consequently increase data transmission rates. The carriercan be a radio frequency (RF) signal having a frequency in a range from300 MHz to 300 GHz, such as in a range from about 500 MHz to about 5 GHzfor radio frequency signals in LTE systems. RF circuits discussed hereincan provide a carrier aggregated RF signal and an indication of power ofan individual carrier of the carrier aggregated signal. Carrieraggregation can be used for both Frequency Division Duplexing (FDD) andTime Division Duplexing (TDD). A plurality of carriers or channels canbe aggregated with carrier aggregation. For instance, up to fivecarriers can be aggregated in certain applications. Carrier aggregationcan be implemented by contiguous aggregation, in which contiguouscarriers within the same operating frequency band are aggregated.Carrier aggregation can alternatively or additionally be non-contiguous,and can include carriers separated in frequency within a common band orin different bands. Advantageously, carrier aggregation can providerelatively high peak data rates, increased data rates for all users in acell, and higher capacity for bursty applications.

Uplink carrier aggregation for Advanced-LTE systems can benefit frompower control of multiple carriers that are transmitted simultaneously.Controlling carrier power such that the combined power of the aggregatedcarrier does not exceed an authorized power specification for a singlecarrier can be advantageous. This can result in, for example, about a 3dB power reduction for each carrier in certain applications, but canvary such that the total power is maintained within a specified limit.

This disclosure provides methods, systems, and apparatus for detectingpower of an individual carrier of an aggregated carrier. As such,separate power measurements can be made for two or more individualcarriers of the aggregated carrier. This can provide accurate powerdetection and control of each individual carrier of an aggregatedcarrier to maintain total power of the aggregated carrier withinspecified limits. Such methods can be implemented in FDD systems and/orTDD systems, in inter-band carrier aggregations and/or intra-bandcarrier aggregations, in carrier aggregations and/or systems withvarious band spacing, in systems with varied target output power, etc.The method of detecting and/or controlling power of an individualcarrier of an aggregated carrier and a corresponding system can bedependent on, among other things, the type of system (e.g., FDD systemvs. TDD system), characteristics of the carrier aggregation (e.g.,intra-band vs. inter-band) and/or particular system specification(s)(e.g., target output power). Any suitable principles and advantages ofthe methods, systems, and/or apparatus discussed herein can beimplemented in a mobile device and/or in connection with an uplinkchannel from a handset to a base station.

According to an embodiment, a carrier aggregation system includes RFsources, such as power amplifiers, a transmission output, and adirectional coupler. Each of the power sources is associated with aseparate carrier. The transmission output can provide a carrieraggregated signal that includes an aggregation of the separate carriersassociated with the RF sources. A directional coupler is arranged toprovide an indication of RF power of one of the separate carriers.

Example system architectures are provided that implement power couplingvia radio frequency (RF) directional couplers, power detection, andclosed loop feedback such that each carrier's RF output power can beregulated to meet system specifications. Packaged electronic componentscan include power amplifiers, directional couplers, and switches inaccordance with one or more of the embodiments discussed herein. Suchpackaged components can also include filters and/or diplexers and/ortriplexers in certain implementations.

FIG. 1A is a schematic diagram of an electronic system 1 for detectingpower of individual carriers of a carrier aggregated signal according toan embodiment. An electronic system arranged to provide a carrieraggregated signal can be referred to as a carrier aggregation system. Asillustrated, the electronic system 1 includes RF sources 2A to 2N,aggregation and processing circuitry 3, and a transmission output 4configured to provide a carrier aggregated signal that includes anaggregation of two or more separate carriers associated with the RFsources. The RF sources 2A to 2N are each associated with a separatecarrier. The RF sources 2A to 2N can each include a power amplifier. Anysuitable number of RF sources 2A to 2N can be implemented. Theaggregation and processing circuitry 3 can receive RF signals from theRF sources 2A to 2N and provide the carrier aggregated signal to thetransmission output 4. The transmission output 4 can be any suitabletransmission output arranged to provide a carrier aggregated signal. Thetransmission output 4 can be electrically coupled to an antenna arrangedto transmit the carrier aggregated signal. The transmission output 4 canbe a terminal of a frequency multiplexer coupled to an antenna. Thetransmission output 4 can be a port of a directional coupler 12 coupledto an antenna.

The aggregation and processing circuitry 3 can include a directionalcoupler 12. A termination impedance 13 (e.g., a termination resistor)can be electrically connected to an isolated port of the directionalcoupler 12. The directional coupler 12 can provide an indication of RFpower of a selected one of the separate carriers at a coupled port CPL.A detection output can be any suitable output for providing anindication of power of an individual carrier of the aggregated carrier.The coupled port CPL of the directional coupler 12 can serve as thedetection output for providing an indication of power of an individualcarrier of the aggregated carrier. In some other implementations, apower detector is coupled to the coupled port CPL of the directionalcoupler and an output of the power detector can serve as the detectionoutput. According to another implementation, an output of a frequencymultiplexing circuit can serve as the detection output, in which thefrequency multiplexing circuit is coupled between a directional couplerand two or more power detectors.

One or more directional couplers of the aggregation and processingcircuitry 3 can be used to implement accurate power detection of eachseparate carrier of the carrier aggregated signal, which can be used tocontrol and/or to maintain total power of the carrier aggregated signalwithin specified limits. The aggregation and processing circuitry 3 caninclude any other suitable circuitry to process signals from the RFsources 2A to 2N and/or to aggregate signals from the RF sources 2A to2N. For instance, in addition to at least one directional coupler 12,the aggregation and processing circuitry 3 can include one or more RFswitches, one or more band limiting filters, one or more duplexers, oneor more frequency multiplexing circuits (e.g., one or more diplexersand/or one or more triplexers), or any combination thereof.

FIGS. 1B and 1C are schematic diagrams of example electronic systems fordetecting power of individual carriers of a carrier aggregated signalaccording to certain embodiments. Each of these electronic systems is anexample of the electronic system 1 of FIG. 1A that includes additionaldetail regarding the aggregation and processing circuitry 3 of FIG. 1Aand also includes an antenna 19. The electronic systems of FIGS. 1B and1C each include RF sources, a transmission output, and at least onedirectional coupler. As illustrated, these systems also include afrequency multiplexing circuit. The RF sources, such as poweramplifiers, are each associated with a separate carrier. Thetransmission output is configured to provide a carrier aggregated signalthat is an aggregation of two or more of the separate carriersassociated with the RF sources. The directional coupler is configured toprovide an indication of RF power of a selected one of the separatecarriers.

FIG. 1B is a schematic diagram of an electronic system 5 for detectingpower of individual carriers of a carrier aggregated signal according toan embodiment. As shown in FIG. 1B, the electronic system 5 includes RFsources 2A and 2B, directional couplers 12A and 12B with terminationimpedances 13A and 13B, respectively, a frequency multiplexing circuit 6(e.g., a diplexer), and an antenna 19. A transmission output 4 canprovide a carrier aggregated signal to the antenna 19, in which thecarrier aggregated signal is an aggregation of the separate carriersassociated with the RF sources 2A and 2B. As illustrated, thetransmission output can be a terminal of the frequency multiplexingcircuit 6 that is electrically coupled to the antenna 19. The carrieraggregated signal can be a FDD carrier aggregated signal or a TDDcarrier aggregated signal.

The directional couplers 12A and 12B can provide an indication of RFpower for individual carriers at coupled ports CPLA and CPLB,respectively. These coupled ports can each serve as a detection outputfor providing an indication of power of an individual carrier of theaggregated carrier provided at the transmission output. The indicationof RF power can also be provided for single carrier cases wherenon-carrier aggregated signals are provided to the antenna 19. Eachdirectional coupler 12A and 12B can be configured for performance at aparticular frequency range associated with a respective carrier of an RFsource 2A and 2B, respectively. Moreover, the directional couplers 12Aand 12B of the electronic system 5 can be arranged such that they shouldnot impact receive paths, if any, associated with the antenna 19.

In FIG. 1B, each of the directional couplers 12A and 12B is disposed ina signal path between an RF source 2A and 2B, respectively, and thefrequency multiplexing circuit 6. While not illustrated in FIG. 1B,there can also be one or more RF switches and a filter in a signal pathbetween each respective directional coupler 12A and 12B and thefrequency multiplexing circuit 6. Examples of such circuits asillustrated in FIGS. 2A to 2C. Moreover, more than two carriers can beaggregated and there can be a similar path for each of the separatecarriers that are aggregated in accordance with the principles andadvantages discussed herein.

FIG. 1C is a schematic diagram of an electronic system 7 for detectingpower of individual carriers of a carrier aggregated signal according toanother embodiment. As shown in FIG. 1C, the electronic system 7includes RF sources 2A and 2B, a frequency multiplexing circuit 6 (e.g.,a diplexer), a directional coupler 12 with a termination impedance 13,and an antenna 19. A carrier aggregated signal provided to the antenna19 can be an aggregation of the separate carriers associated with the RFsources 2A and 2B. As illustrated, the transmission output can be a portof the directional coupler 12 electrically coupled to the antenna 19.The carrier aggregated signal can be a TDD carrier aggregated signal.

A single directional coupler 12 can provide an indication of RF powerfor an individual carrier at coupled port CPL associated with theindividual carrier being provided to the antenna 19. The electronicsystem 7 can be implemented with a single direction coupler 12 that canprovide an indication of power associated with each individual carrierof a carrier aggregated signal provided by the frequency multiplexingcircuit 6. In certain implementations, such as applications with TDDcarrier aggregation with non-overlapping transmission, a single powerdetector can be implemented in connection with the directional coupler12 to detect power associated with each individual carrier of a carrieraggregated signal. According to some other implementations, such asapplications with TDD carrier aggregation with overlapping transmission,there can be a duplexer, duplex filter, or the like disposed between thedirectional coupler 12 and a plurality of power detectors.

As shown in FIG. 1C, the directional coupler 12 is disposed in a signalpath between the frequency multiplexing circuit 6 and the antenna 19.While not illustrated in FIG. 1C, there can also be other circuitelements, such as one or more RF switches, in a signal path between thedirectional coupler 12 and the antenna 19. Examples of such circuits areillustrated in FIG. 4A. Moreover, there can be additional circuitrydisposed in a signal path between the RF sources 2A and 2B,respectively, and the frequency multiplexing circuit 6. Examples of suchfeatures as illustrated in FIGS. 3B and 4A.

Inter-band carrier power detection for FDD and/or TDD systems can beimplemented using a plurality of directional couplers located in signalpaths of individual carriers of an aggregated carrier. Each directionalcoupler can be disposed between a respective power amplifier of anindividual carrier and one or more corresponding band-limiting filters,which can be band pass filters. A band-limiting filter can isolate aradio frequency signal associated with a respective power amplifier froma radio frequency signal from one or more other power amplifiers.Band-limiting filters can mitigate out of band emissions, filter outreceive band noise, reject out of band blockers which can createintermodulation (IM) products within the power amplifier, the like, orany combination thereof. This can be prevalent from the alternatetransmission in carrier aggregation and such IM products can causeinterference with other transmissions and/or receptions. Havingdirectional couplers between a power amplifier output and aband-limiting filter can enable simultaneous power measurements to bemade for each carrier without interference from one or more of the othercarriers.

FIGS. 2A to 2C illustrate example electronic systems that include adirectional coupler in a signal path between a power amplifier for eachcarrier and a respective band limiting filter. Any suitable principlesand advantages of the embodiments discussed with reference to FIGS. 2Ato 2C can be implemented in connection with each other and/or inconnection with any other embodiments discussed herein. An electronicsystem that includes a power amplifier can be referred to as a poweramplifier system.

FIG. 2A is a schematic diagram of an electronic system 10 with carrieraggregation and power detection of individual carriers according to anembodiment. The electronic system 10 can implement inter-band carrierpower detection for FDD and/or TDD. In the electronic system 10, adirectional coupler is disposed between a power amplifier and an RFswitch, such as band select switch or a transmit/receive switch. Eachdirectional coupler can be arranged for enhanced and/or optimizedperformance for a particular frequency range associated with arespective carrier. In the electronic system 10, the illustrateddirectional couplers 12 should not contribute to insertion loss betweenthe antenna 19 and any receive paths (not illustrated).

The illustrated electronic system 10 includes power amplifiers 11A, 11B,directional couplers 12A, 12B, termination impedances 13A, 13B, powerdetectors 14A, 14B, RF switches 8A, 8B, filters 9A, 9B, antenna switch17, frequency multiplexing circuit 6, and an antenna 19. A first poweramplifier 11A and a second power amplifier 11B can provide radiofrequency (RF) signals that can be aggregated at a transmission output,such as the output of the frequency multiplexing circuit 6, fortransmission by the antenna 19. The power amplifiers 11A and 11B areexamples of RF sources that provide RF signals. The first poweramplifier 11A can be associated with a first carrier. The first poweramplifier 11A can receive a first carrier and a first input signal andprovide a first amplified RF signal. The second power amplifier 11B canbe associated with a second carrier that is separate from the firstcarrier.

Power associated with the first amplified RF signal provided by thefirst power amplifier 11A can be detected using a first directionalcoupler 12A and a first power detector 14A. Any suitable terminationimpedance 13A, such as a 50 Ohm terminating resistor, can beelectrically connected to the first directional coupler 12A. Asillustrated, the first directional coupler 12A can be disposed in asignal path between the first power amplifier 11A and a filter 9A. An RFswitch 8A can selectively electrically connect the first power amplifier11A to the filter 9A.

Power associated with a second amplified RF signal provided by thesecond power amplifier 11B can be detected using the second directionalcoupler 12B. The second power detector 14B can provide an indication ofpower of the second carrier in the electronic system 10. The seconddirectional coupler 12B and the second power detector 14B can detectpower associated with the RF signal provide by the second poweramplifier 11B. An RF switch 8B can selectively electrically connect thesecond power amplifier 11A to the filter 9B. The filters 9A and 9B canhave different pass bands. For instance, the pass bands of the filters9A and 9B can correspond to different sub-bands within a transmit banddefined by an LTE standard and/or to different transmit bands defined byan LTE standard. The RF switches 8A and 8B can be multi-throw RFswitches.

The antenna switch 17 can selectively electrically connect the firstfilter 9A and/or the second filter 9B to the frequency multiplexingcircuit 6. The frequency multiplexing circuit 6 can provide a carrieraggregated signal to the antenna 19 for transmission.

FIG. 2B is a schematic diagram of an electronic system 10′ with uplinkcarrier aggregation and power detection of individual carriers accordingto an embodiment. The electronic system 10′ can implement inter-bandcarrier power detection for FDD and/or TDD. In the electronic system10′, a directional coupler is disposed between a multimode, multi-band(MMMB) power amplifier and a band select switch. The circuit shown inFIG. 2B can provide a coupled power path associated with individualcarriers in carrier aggregation operations and also for single carrieroperations. Each directional coupler can be arranged for enhanced and/oroptimized performance for a particular frequency range associated with arespective carrier. For instance, a termination impedance provided to anisolated port of a directional coupler can be selected to have animpedance associated with a particular frequency range of an RF signalprovided by a corresponding power amplifier. In the electronic system10′, there is no directional coupler between the antenna and receivepaths. This can reduce loss associated with receiving signals from theantenna.

The illustrated electronic system 10′ includes power amplifiers 11A,11B, directional couplers 12A, 12B, termination impedances 13A, 13B,power detectors 14A, 14B, band select switches 15A, 15B, duplexers 16A,16B, antenna switches 17A, 17B, diplexer 18, and an antenna 19. In thecircuit shown in FIG. 2B, a first power amplifier 11A and a second poweramplifier 11B can provide radio frequency (RF) signals that can beaggregated for transmission by the antenna 19. FIG. 2B illustrates thefrequency domains of example signals provided by the power amplifiers11A and 11B and the frequency domain of an example carrier aggregatedtransmit signal provided to the antenna 19. The power amplifiers 11A and11B are examples of RF sources that provide RF signals. The first poweramplifier 11A can be associated with a first carrier. The first poweramplifier 11A can receive a first carrier and a first input signal andprovide a first amplified RF signal. The second power amplifier 11B canbe associated with a second carrier that is separate from the firstcarrier.

Power associated with the first amplified RF signal provided by thefirst power amplifier 11A can be detected using a first directionalcoupler 12A and a first power detector 14A. Any suitable terminationimpedance 13A, such as a 50 Ohm terminating resistor, can beelectrically connected to the first directional coupler 12A. Asillustrated, the first directional coupler 12A can be disposed in asignal path between the first power amplifier 11A and a transmit bandpass filter of the first duplexer 16A. As illustrated, the firstduplexer 16A also includes a receive filter. The band select switch 15Acan selectively electrically connect the first power amplifier 11A orother circuit element(s) to the transmit band pass filter of the firstduplexer 16A.

Power associated with a second amplified RF signal provided by thesecond power amplifier 11B can be detected at the same time as powerassociated with the first amplified RF signal provided by the firstpower amplifier 11A. In the electronic system 10′, the first directionalcoupler 12A can provide an indication of power of the first carrier anda second directional coupler 12B can provide an indication of power ofthe second carrier. In addition, the first power detector 14A providesan indication of power of the first carrier and the second powerdetector 14B provides an indication of power of the second carrier inthe electronic system 10′. The second directional coupler 12B and thesecond power detector 14B can detect power associated with the RF signalprovide by the second power amplifier 11B. As illustrated in FIG. 1, thesecond directional coupler 12B can be disposed in a signal path betweenthe second power amplifier 11B and a transmit band pass filter of thesecond duplexer 16B. The transmit band pass filter of the secondduplexer 16B can have a different pass band than the transmit band passfilter of the first duplexer 16A. For instance, the pass bands of thetransmit band pass filters of the duplexers 16A and 16B can correspondto different sub-bands within a transmit band defined by an LTEstandard. The band select switch 15B can selectively electricallyconnect the second power amplifier 11B or other circuit element(s) tothe transmit band pass filter of the second duplexer 16B. The bandselect switches 15A, 15B can be multi-throw, RF switches.

In the illustrated electronic system 10′, relatively high isolation ofeach detected carrier signal from the other carrier can be provided dueto isolation provided by one or more of (1) out-of-band filtering ofeach duplexer 16A/16B, (2) out-of-band isolation of the antenna diplexer18, and (3) the directivity of a forward port of the directional coupler12A or 12B to the reverse-traveling wave of the residual interferingcarrier.

A first antenna switch 17A can selectively electrically connect thefirst duplexer 16A or other circuit elements (e.g., another duplexerassociated with a different band of operation) to the diplexer 18. Asecond antenna switch 17B can selectively electrically connect thesecond duplexer 16B or other circuit elements to the diplexer 18. Thediplexer 18 is a frequency domain multiplexing circuit that canimplement frequency domain multiplexing of the RF signals received fromthe duplexers 16A and 16B, for example, by way of the antenna switches17A and 17B, respectively.

The electronic system 10′ illustrates FDD duplex filters combined viathe diplexer 18. Any suitable principles and advantages discussed withreference to the electronic system 10′ can be implemented in connectionwith other electronic systems, such as TDD aggregation systems withsurface acoustic wave (SAW) filter(s), bulk acoustic wave (BAW)filter(s), and/or thin-film bulk acoustic resonator (FBAR) filter(s)with an additional transmit/receive switch for each band and/or anadditional transmit/receive throw in each band select switch.

FIG. 2C is a schematic diagram of an electronic system 10″ with carrieraggregation and power detection of individual carriers according toanother embodiment. The electronic system 10″ is like the electronicsystem 10 of FIG. 2A in which the RF switches 8A and 8B of FIG. 2A areimplemented by transmit/receive switches 21A and 21B, respectively, anantenna switch 17 is not shown, and the frequency multiplexing circuit 6of FIG. 2A is implemented by a diplexer 18. The electronic system 10″ islike the electronic system 10′ of FIG. 2B except that transmit/receiveswitches 21A and 21B are implemented in place of band select switches15A and 15B, respectively, corresponding changes are made to the signalpaths between the switches and the diplexer 18, and an antenna switch 17is not shown. Some embodiments of the electronic system 10″ can includean antenna switch 17 in signal paths between filters 9A and 9B and thediplexer 18.

The electronic system 10″ includes filters 9A and 9B in signal pathsbetween the transmit/receive switches 21A and 21B and respective portsof the diplexer 18. By contrast, the electronic system 10′ of FIG. 2Bincludes a plurality of duplexers and RF switches electrically coupledbetween the band select switches 15A and 15B and respective ports of thediplexer 18 of FIG. 2B. The electronic system 10″ also illustrates lownoise amplifiers 22A and 22B of receive paths. The filters 9A and 9Bshown in FIG. 2C can each be targeted to pass frequencies associatedwith a particular carrier. For instance, the filter 9A can be configuredto pass frequencies associated with a Band 39 carrier in certainimplementations. According to some such implementations, the diplexer 18can provide a carrier aggregated signal to the antenna, in which thecarrier aggregated signal aggregates a Band 39 carrier with a Band 41carrier.

The electronic systems discussed herein, such as the electronic systemsof FIGS. 2A to 2C can be implemented in a variety of electronic modules.An electronic module configured to process an RF signal can be referredto as a radio frequency module. An electronic module that includes oneor more power amplifiers can be referred to as a power amplifier module.Electronic modules can be packaged modules that include a plurality ofcomponents on a package substrate. Some such packaged modules can bemulti-chip modules. FIGS. 2D, 2E, 2F, and 2G are schematic diagrams ofexample electronic modules according to certain embodiments. Electronicmodules can be implemented in accordance with any of the principles andadvantages discussed herein. Some or all of the features of any of theelectronic systems discussed herein can be implemented in an electronicmodule.

FIG. 2D is a schematic diagram of an example electronic module 25according to an embodiment. The electronic module 25 can implement partof the electronic system 10″ of FIG. 2C. As illustrated, the electronicmodule 25 includes a power amplifier 11, a directional coupler 12 with atermination impedance 13, a transmit/receive switch 21, and a controlcircuit 26. The electronic module 25 has a contact RF_IN (e.g., pin,bump, or the like) configured to receive an RF input for transmission.The electronic module 25 has a contact CPL_OUT arranged to provide anindication of RF power associated with the RF signal provided by thepower amplifier 11, a contact RX arranged to provide a receive signal,and a contact RF_OUT configured to provide an RF transmission output. Inone application, the electronic module 25 can be used to provide a band39 carrier in a band 39/band 41 uplink carrier aggregation system.

FIG. 2E is a schematic diagram of an example electronic module 25′according to an embodiment. The electronic module 25′ can implement partof the electronic system 10′ of FIG. 2B. As illustrated, the electronicmodule 25′ includes power amplifiers 11A and 11B, directional couplers12A and 12B with a termination impedances 13A and 13B, respectively,power detectors 14A and 14B, and RF switches 15A and 15B.

FIG. 2F is a schematic diagram of an example electronic module 25″according to an embodiment. The electronic module 25″ can implement partof the electronic system 10′ of FIG. 2B. The electronic module 25″ islike the electronic module 25′ of FIG. 2E except that the electronicmodule 25″ also includes filter banks 27A and 27B. The filter banks 27Aand 27B can implement any suitable filtering. For instance, the filterbanks 27A and 27B can each implement a bank of transmit filters. Asanother example, the filter banks 27A and/or 27B can implement transmitand receive filters. In an embodiment, the filter banks 27A and 27B canimplement the duplexers of the electronic system 10′ of FIG. 2B.

FIG. 2G is a schematic diagram of an example electronic module 25′″according to an embodiment. The electronic module 25′″ can implementpart of the electronic system 10′ of FIG. 2B. The electronic module 25′″is like the electronic module 25″ of FIG. 2F except that the electronicmodule 25′″ also includes antenna switches 17A and 17B.

In TDD systems, a single directional coupler can detect RF powerassociated with each carrier when a transmit slot timing of each carrierdoes not overlap with another carrier. Accordingly, each carrier cantransmit while another channel is in a receive mode or a standby mode.This can implement precise power detection for non-overlappingtransmission TDD systems.

FIGS. 3A and 3B are a schematic diagram of electronic systems withuplink carrier aggregation and power detection of individual carriersaccording to certain embodiments. These electronic systems can implementpower detection of individual carriers of an aggregated carrier insystems configured to transmit non-overlapping transmit TDD carrieraggregation signals. When carrier aggregation is controlled in such away that transmissions associated with individual carriers do notoverlap, effective uplink and downlink data rates can be increased.Power of individual carriers can be detected at different times and anindication of the detected power of each carrier can be used to controlpower of the respective carrier. TDD with non-overlapping transmissioncan limit peak power supply/battery current by having only one poweramplifier on at a time. The electronic systems of FIGS. 3A and 3B eachinclude a single directional coupler 12 and a single power detector 14to provide indications of power of individual carriers for providing aclosed loop power control of each carrier. According to certainembodiments, the systems of FIGS. 3A and/or 3B can operate in a carrieraggregation mode and in a single carrier mode. Since only one TDDcarrier may transmit at any given time in such systems, one directionalcoupler 12 may be used for either a single carrier signal or anaggregated carrier signal in certain implementations.

FIG. 3A is a schematic diagram of an electronic system 20 with uplinkcarrier aggregation and power detection of individual carriers accordingto an embodiment. As illustrated, the electronic system includes a TDDpath 28, RF paths 29A to 29N, an antenna switch 24, a directionalcoupler 12 with a termination impedance 13, a power detector 14, and anantenna 19. The TDD path 28 is configured to provide a TDD carrieraggregated signal to the antenna switch 24. The TDD carrier aggregatedsignal can be a non-overlapping TDD carrier aggregated signal. RF signalpaths 29A to 29N can each provide an RF signal to the antenna switch 24when active. Any suitable number of RF signal paths can be implemented.The RF signal paths 29A to 29N can be TDD carrier aggregation signalpaths and/or FDD carrier aggregation signal paths. The antenna switch 24can electrically couple a selected signal path to the antenna 19. In afirst state, the antenna switch 24 can electrically couple the TDD path28 to the antenna 19. When the antenna switch 24 is in the first state,the directional coupler 12 can provide an indication of RF powerassociated an individual carrier being transmitted by the TDD path 28.The directional coupler 12 can also provide an indication of powerassociated with an RF path 29A to 29N that is electrically coupled tothe antenna 19 in different states of the antenna switch 24.

FIG. 3B is a schematic diagram of an electronic system 20′ with uplinkcarrier aggregation and power detection of individual carriers accordingto an embodiment. The electronic system 20′ can implement powerdetection of individual carriers of an aggregated carrier in anon-overlapping transmission TDD carrier aggregation system. Theillustrated electronic system 20′ includes power amplifiers 11A, 11B,transmit/receive switches 21A/21B, low noise amplifiers 22A/22B, bandpass filters 23A, 23B, a diplexer 18, RF signal paths 29A, 29B, and 29C,an antenna switch 24, a directional coupler 12, a termination impedance13, a power detector 14, and an antenna 19. FIG. 3C is an illustrativediagram of timing of time division duplexing with non-overlappingtransmission and associated power consumption in the electronic system20′ of FIG. 3B. An RF path associated with a first carrier can be intransmit mode as illustrated when the first transmit/receive switch 21Ais in a state corresponding to transmit mode and the secondtransmit/receive switch 21B is in a state corresponding to receive mode.The transmit/receive switches 21A and 21B can alternate between transmitand receive modes in accordance with the timing diagram of FIG. 3C. Thedirectional coupler 12 can provide an indication of RF power associatedwith a first carrier when the first carrier is being transmitted via theantenna 19 and provide an indication of RF power associated with thesecond carrier when the second carrier is being transmitted via theantenna 19. Based on a signal indicative of the transmit/receive modesof the first carrier and the second carrier, a power control system(e.g., a power control system of FIG. 6A or a power control system ofFIG. 6C) can detect which carrier of the aggregated carrier isassociated with an output of the directional coupler 12 and an output ofthe power detector 14.

As shown in FIG. 3B, the antenna switch 24 can electrically couple theTDD carrier aggregation signal path 28 to the antenna 19. The antennaswitch 24 can electrically couple a selected one of the RF signal paths29A, 29B, or 29C to the antenna 19 in other states. Any of the RF signalpath 29A to 29C can implement, for example, a non-overlapping TDDcarrier aggregation signal path like the TDD carrier aggregation signalpath 28. Alternatively or additionally, any of the RF signal paths 29Ato 29C can implement an overlapping TDD carrier aggregation signal path,a FDD carrier aggregation signal path, or a single carrier signal path.

The illustrated electronic system 20′ can be implemented with individualSAW filters combined via the diplexer 18. Any suitable principles andadvantages discussed with reference to the electronic system 20′ can beimplemented in connection with other electronic systems, such electronicsystems with a single SAW duplexer, a single BAW duplexer, or a singleFBAR duplexer.

In TDD systems where transmission of both carriers can occur at the sametime, a single directional coupler can detect RF power associated witheach carrier when coupled signals are separated by way of a diplexerand/or a duplex filter. Separate power detectors can receive coupledsignals associated with separate carriers. Each of the separate powerdetectors can be a relatively simple power detector in certainimplementations rather than a more complex tuned receiver-based powerdetector.

FIG. 4A is a schematic diagram of an electronic system 30 with uplinkcarrier aggregation and power detection of individual carriers accordingto an embodiment. The electronic system 30 can implement power detectionof individual carriers of an aggregated carrier in a TDD system in whichindividual carriers are simultaneously transmitted. Having a relativelylow power duplexer or diplexer filter electrically connected to acoupled port of a directional coupler can allow each aggregated carrierto be separated and processed independently for controlling the power ofeach carrier. Insertion loss of the carrier aggregated directionalcoupler 12 can only impact carrier aggregated path 32 in the electronicsystem 30. Accordingly, other RF signal paths 29A to 29C should not beimpacted by the insertion loss of the illustrated directional coupler12. Including other standard carriers should not add additional loss orcomplexity.

The illustrated electronic system 30 includes the carrier aggregatedpath 32, the other RF signal paths 29A to 29C, an antenna switch 37, andthe antenna 19. As illustrated, the carrier aggregated path 32 includespower amplifiers 11A, 11B, transmit/receive switches 21A/21B, low noiseamplifiers 22A/22B, band pass filters 23A, 23B, a diplexer 18, adirectional coupler 12, a termination impedance 13, and a powerdetection diplexer 31. In the electronic system 30, the antenna selectswitch 32 can be disposed in a signal path between the directionalcoupler 12 and the antenna 19. The antenna select switch 32 canelectrically couple a selected signal path to the antenna 19. The otherRF signal paths 29A to 29C can be implemented in accordance with any ofthe principles and advantages associated with RF signal paths discussedherein. One or more of the other RF signal paths 29A to 29C can becarrier aggregated signal paths. Alternatively or additionally, one ormore of the other RF signal paths 29A to 29C can be single carriersignal paths.

FIG. 4B is an illustrative diagram of timing of time division duplexingwith overlapping transmission and associated power consumption in theelectronic system 30 of FIG. 4A. As shown in FIG. 4B, a first RF pathassociated with a first carrier and a second RF path associated with asecond carrier can be in transmit mode at the same time. These two RFpaths can be included in the carrier aggregated path 32 of FIG. 4A. Anindication of RF power of the aggregated carrier can be provided by thedirectional coupler 12. The diplexer 31 can frequency multiplex theindication of RF power of the aggregated carrier to provide anindication of RF power of the first carrier to a first power detectorand an indication of RF power of the second carrier to a second powerdetector.

The illustrated electronic system 30 can be implemented with individualSAW filters combined via the diplexer 18. Any suitable principles andadvantages discussed with reference to the electronic system 30 can beimplemented in connection with other electronic systems, such electronicsystems with a single SAW duplexer, a single BAW duplexer, or a singleFBAR Duplexer.

In TDD systems and/or FDD systems transmitting an inter-band carrieraggregated signal that includes carriers associated with more than oneband, a power control method can be implemented using independentdirectional couplers located in a signal path between a power amplifierand a sub-band frequency limiting filter. Examples of more than one bandthat can be aggregated include, but are not limited to, (a) low band(LB) (e.g., 699 MHz-915 MHz) and mid band (MB) (e.g., 1710 MHz-2025MHz), (b) LB and high band (HB) (e.g., 2300 MHz-2695 MHz), and (c) MBand HB. Sub-band frequency limiting filtering can be implemented by adiplexer used to combine LB and MB, a duplexer or multiple duplexers andband select switch, TDD band limiting filters, a LB and MB and HBtriplexer, power isolation via antenna separation, the like or anycombination thereof.

FIG. 5A is a schematic diagram of an electronic system 40 with uplinkcarrier aggregation and power detection of individual carriers accordingto an embodiment. The electronic system 40 can implement power detectionof individual carriers of an aggregated carrier in a TDD and/or FDDsystem. A frequency multiplexing circuit, such as a diplexer or atriplexer, can provide isolation between low band, mid band and highband frequencies to isolate the directional couplers associated withindividual carriers from the alternate aggregated carrier associatedwith two or more other individual carriers. A switch may be used toselect between different directional couplers in systems with fewerpower detectors than directional couplers. Each directional coupler canbe configured for enhanced and/or optimized performance for a particularfrequency range (e.g., the low band, mid band or high band frequencyranges) to improve performance.

The illustrated electronic system 40 includes power amplifiers 11A, 11B,11C, switches 41A, 41B, 41C, duplexers 42A, 42B, 42C, switches 43A, 43B,43C, directional couplers 12A, 12B, 12C, termination impedances 13A,13B, 13C, select switch 44, power detector 14, triplexer 45, and antenna19. The power amplifiers 11A, 11B, and 11C can each transmit anamplified RF signal associated with a different carrier. Switches 41A,41B, and 41C together with respective switches 43A, 43B, and 43C canelectrically couple respective power amplifiers 11A, 11B, and 11C torespective directional couplers 12A, 12B, and 12C by way of duplexers42A, 42B, and 42C. Duplexers 42A can be implemented by a bank ofduplexers that are each associated with a different frequency bandsand/or other filtering characteristics (e.g., out of band attenuation,in band attenuation, etc.). Similarly, duplexers 42B and/or 42C can beimplemented by a bank of duplexers that are each associated with adifferent frequency bands and/or other filtering characteristics (e.g.,out of band attenuation, in band attenuation, etc.).

Directional couplers 12A, 12B, and 12C can each provide an indication ofRF power associated with a respective carrier. Termination impedances13A, 13B, and 13C can be configured to enhance and/or optimizeperformance of a respective directional coupler for frequency of acarrier associated with the respective directional coupler. The selectswitch 44 can electrically couple a selected directional coupler 12A,12B, or 12C to the power detector 14. As such, the switch 44 can be usedto share a single power detector 14 among a plurality of directionalcouplers 12A, 12B, and 12C. With other switch arrangements, directionalcouplers can be arranged to utilize two detectors for variouscombinations of inter-band carrier aggregation, such as (a) LB and MB,(b) LB and HB, or (c) MB and HB. In another embodiment (notillustrated), a separate power detector can be provided for eachdirectional coupler 12A, 12B, and 12C. The triplexer 45 is a frequencymultiplexing circuit that can provide isolation between a carrieraggregated signal and RF signals associated with individual carriers.

In the illustrated electronic system 40, relatively high isolation ofeach detected carrier signal from the other carrier can be provided dueto isolation provided by (1) out-of-band filtering of each duplexer 42A,42B, and 42C, (2) out-of-band isolation of the antenna triplexer 45, and(3) the directivity of a forward port of a selected directional coupler12A or 12B or 12C to the reverse-travelling wave of the residualinterfering carrier(s).

FIG. 5B is a schematic diagram of an electronic system 40′ with carrieraggregation and power detection of individual carriers according to anembodiment. The electronic system 40′ can be implemented in downlinkcarrier aggregation systems, for example. As illustrated, the electronicsystem 40′ includes power amplifiers 11A and 11B, filters 46A and 46Bconfigured to filter outputs of the power amplifiers 11A and 11B,respectively, switches 43A, 43B, and 43C, directional couplers 12A, 12B,and 12C, coupler terminations 47A, 47B, and 47C, select switch 44, anddiplexer 18.

The electronic system 40′ includes circuits that are similar to theelectronic system 40 of FIG. 5A. The electronic system 40′ includes thediplexer 18 to combine two of the three illustrated paths associatedwith individual carriers, such as LB and MB carrier paths. In contrast,the electronic system 40 of FIG. 5A includes a triplexer 45 to combinethree paths associated with individual carriers.

A coupled out output port CPL can provide an indication to a detector,which is not illustrated in FIG. 5B. Any of the detectors discussedherein can be implemented internal or external to an electronic moduleor device than an associated directional coupler, depending on aparticular application.

The coupler terminations 47A, 47B, and 47C associated with directionalcouplers 12A, 12B, and 12C, respectively, can enable these directionalcouplers to provide an indication of forward power in one state and anindication of reverse power in another state. For instance, the couplerterminations 47A, 47B, and 47C can provide respective terminationimpedances to different coupler ports in different states. Such featurescan be implemented with any other embodiments discussed herein assuitable.

FIG. 5C is a schematic diagram of an electronic system 40″ with carrieraggregation and power detection of individual carriers according to anembodiment. The electronic system 40″ can be implemented in downlinkcarrier aggregation systems, for example. The electronic system 40″includes circuits that are similar to the electronic system 40′ of FIG.5B. Some differences between the electronic system 40″ and theelectronic system 40′ include that the electronic system 40″ providesLB, MB, and HB outputs that can allow more flexibility in combiningcarriers in a path to an antenna and there are a plurality of coupledout output ports CPL1 and CPL2. With two coupled out output ports CPL1and CPL2, select switches 44A and 44B can provide outputs of two of thethree illustrated directional couplers to two power detectors. FIG. 5Cillustrates that a notch filter 47 can be included in a signal pathbetween a power amplifier 22A and a directional coupler 12B in certainembodiments. FIG. 5C illustrates that outputs of directional couplers12B and 12C can be filtered by a band pass filter 48 and a low passfilter 49, respectively, in signal paths between directional couplers12B and 12C and a frequency multiplexing circuit and/or an antenna.

FIG. 6A is a schematic diagram of a carrier aggregation system 50 withclosed loop power control according to an embodiment. An indication ofRF power associated with an individual carrier can be used to control apower of an individual carrier in a carrier aggregation system based ona detected power of the individual carrier. The illustrated electronicsystem 50 includes power detection and feedback control circuit 54,modems 55A to 55N, amplifiers 56A to 56N, carrier aggregation circuit57, and antenna 19. The feedback control circuit 54, modems 55A to 55N,and amplifiers 56A to 56N can together implement a power control system.The carrier aggregation circuit 57 can include any suitable carrieraggregation signal path discussed herein. The carrier aggregationcircuit 57 can provide an indication of power associated with anindividual carrier of a carrier aggregated signal. The power detectionand feedback control circuit 54 can adjust a power level associated withan amplifier of the amplifiers 56A to 56N that is associated with theindividual carrier based on the indication of power associated with theindividual carrier. By adjusting a power level associated with aselected amplifier of the amplifiers 56A to 56N, a power level of an RFsource, such as a power amplifier, of the carrier aggregation circuit 57can accordingly be adjusted.

FIG. 6B is a flow diagram of an illustrative process 60 of controllingpower of individual carriers of a carrier aggregated signal according toan embodiment. Some or all of the process 60 can be implemented with anyof the embodiments discussed herein as suitable. The process 60 can beperformed on a mobile device. It will be understood that any of themethods discussed herein may include more or fewer operations thanillustrated on a flow diagram and the operations may be performed in anyappropriate order.

At block 62, power of an individual carrier of an aggregated carrier isdetected. Detecting power of the individual carrier can involve using apower detector coupled to any suitable directional coupler discussedherein. As one example, detecting the indication of power of theindividual carrier can be based on an output of a directional couplercoupled between a frequency multiplexing circuit and an antenna. Asanother example, detecting the indication of power of the individualcarrier can be based on an output of a directional coupler coupledbetween a power amplifier and a multi-throw radio frequency switch. Thepower associated with the individual carrier can be adjusted based onthe detected power associated with the individual carrier at block 64.For instance, the power associated with a selected amplifier of theamplifiers 56A to 56N of FIG. 6A can be adjusted using a control signalprovided a power detector and feedback control circuit 54 of FIG. 6A.

At block 66, power of a different individual carrier of the aggregatedcarrier is detected. Detecting power of the different individual carrierat block 66 can involve a different directional coupler than detectingpower of the individual carrier at block 62 in certain embodiments.Detecting power of the different individual carrier at block 66 caninvolve the same directional coupler as detecting power of theindividual carrier at block 62 in some other embodiments. Powerassociated with the different individual carrier can be adjusted basedon the detected power associated with the different individual carrierat block 68. Accordingly, power associated with a plurality ofindividual carriers of a carrier aggregated signal can be adjusted basedon detected power associated with respective individual carriers.

FIG. 6C is a schematic diagram of a carrier aggregation system 50′ withclosed loop power control 50 according to an embodiment. An indicationof RF power associated with an individual carrier provided by adirectional coupler, a power detector, or a duplexer, etc. can be usedto control power of an RF signal provided to an RF source, such as apower amplifier. The illustrated system 50′ includes a power controlsystem 53. As shown in FIG. 6C, a directional coupler 12 can provide anindication of RF power of an individual carrier or a carrier aggregatedsignal to a power detector and feedback control circuit 54. The powerdetector and feedback control circuit 54 can include a power detector,such as a power detector 14, and a feedback control circuit configuredto generate a control signal based at least partly on the indication ofRF power of the individual carrier. A modem 55A, 55B, or 55C can providea carrier signal to an amplifier 56A, 56B, 56C, respectively. A power ofthe output of an amplifier 56A, 56B, or 56C can be controlled by acontrol signal provided by the power detector and feedback controlcircuit 54. This can control a power of an individual carrier in acarrier aggregation system based on a detected power of the individualcarrier. Any of these principles and advantages can be applied tocontrolling power of two or more individual carriers associated with acarrier aggregated signal. In certain embodiments, the principles andadvantages discussed herein can be applied to control power of eachcarrier of a carrier aggregated signal. Any of the carrier aggregatedsignals discussed herein can be an aggregation associated with two ormore carriers.

FIG. 7 is a schematic block diagram of an example wireless communicationdevice 70 that can include any suitable combination of features relatedto the power detection of an individual carrier of a carrier aggregatedsignal discussed herein. The wireless communication device 70 can be anysuitable wireless communication device. For instance, this device can bea mobile phone such as a smart phone. As illustrated, the wirelesscommunication device 70 includes an antenna 19, an RF front end 72, apower control system 52, a processor 74, and memory 76. Any of thecarrier aggregated signal paths and/or carrier aggregation circuitsdiscussed herein can be implemented in the RF front end 72. The RF frontend 72 can provide a carrier aggregated RF signal to the antenna 19 fortransmission. The RF front end 72 can also process an RF signal receivedby the antenna 19. The memory 76 can store data on the wirelesscommunication device 70. The processor 74 can store and/or access datain the memory 76. The processor 74 can process baseband signals. Asillustrated, the power control system 53 is coupled between theprocessor 74 and the RF front end 72. The power control system 53 canimplement any of the principles and advantages discussed in connectionwith any of FIGS. 6A to 6C.

Some of the embodiments described above have provided examples inconnection with power amplifiers and/or mobile devices. However, theprinciples and advantages of the embodiments can be used for any othersystems or apparatus that could benefit from any of the principles andadvantages described herein. For instance, power amplifiers are examplesof RF sources that provide RF signals and any suitable combination offeatures discussed herein can be implemented in connections with otherRF sources. Any of the principles and advantages discussed herein can beimplemented in an electronic system with a need for detecting and/orcontrolling a power level of an individual carrier of an aggregatedcarrier. While embodiments may have been discussed above with referenceto uplink carrier aggregated systems, any suitable principles andadvantages discussed herein can be applied to downlink carrieraggregation systems. Any suitable principles and advantages of anembodiment discussed with reference to a particular type or types ofcarrier aggregation (e.g., FDD, TDD with non-overlapping transmission,TDD with overlapping transmission) can be implemented in connection witha different type of carrier aggregation as suitable. Any suitableprinciples and advantages of an embodiment discussed with reference tointer-band carrier aggregation can be implemented in connection withintra-band carrier aggregation as suitable. The teachings herein areapplicable to a variety of power amplifier systems including systemswith multiple power amplifiers, including, for example, multi-bandand/or multi-mode power amplifier systems. The power amplifiertransistors discussed herein can be, for example, gallium arsenide(GaAs), complementary metal oxide semiconductor (CMOS), or silicongermanium (SiGe) transistors. Moreover, power amplifiers discussedherein can be implemented by FETs and/or bipolar transistors, such asheterojunction bipolar transistors.

Aspects of this disclosure can be implemented in various electronicdevices. Examples of the electronic devices can include, but are notlimited to, consumer electronic products, parts of the consumerelectronic products, electronic test equipment, cellular communicationsinfrastructure such as a base station, etc. Examples of the electronicdevices can include, but are not limited to, a mobile phone such as asmart phone, an electronic module configured for use in a mobile phone,an electronic module configured for use in a base station, a telephone,a television, a computer monitor, a computer, a modem, a hand-heldcomputer, a laptop computer, a tablet computer, an electronic bookreader, a wearable computer such as a smart watch, a personal digitalassistant (PDA), a microwave, a refrigerator, an automobile, a stereosystem, a DVD player, a CD player, a digital music player such as an MP3player, a radio, a camcorder, a camera, a digital camera, a portablememory chip, a health care monitoring device, a vehicular electronicssystem such as an automotive electronics system or an avionicselectronic system, a washer, a dryer, a washer/dryer, a peripheraldevice, a wrist watch, a clock, etc. Further, the electronic devices caninclude unfinished products.

Unless the context clearly requires otherwise, throughout thedescription and the claims, the words “comprise,” “comprising,” and thelike are to be construed in an inclusive sense, as opposed to anexclusive or exhaustive sense; that is to say, in the sense of“including, but not limited to.” The words “electrically coupled”, asgenerally used herein, refer to two or more elements that may be eitherdirectly electrically connected, or electrically connected by way of oneor more intermediate elements. Likewise, the word “connected”, asgenerally used herein, refers to two or more elements that may be eitherdirectly connected, or connected by way of one or more intermediateelements. A radio frequency signal can have a frequency in the rangefrom 300 MHz to 300 GHz. Additionally, where appropriate, the words“herein,” “above,” “below,” and words of similar import, when used inthis application, shall refer to this application as a whole and not toany particular portions of this application. Where the context permits,words in the above Detailed Description of Certain Embodiments using thesingular or plural number may also include the plural or singularnumber, respectively. The word “or” in reference to a list of two ormore items, where context permits, covers all of the followinginterpretations of the word: any of the items in the list, all of theitems in the list, and any combination of the items in the list.

Moreover, conditional language used herein, such as, among others,“can,” “could,” “might,” “may,” “e.g.,” “for example,” “such as” and thelike, unless specifically stated otherwise, or otherwise understoodwithin the context as used, is generally intended to convey that certainembodiments include, while other embodiments do not include, certainfeatures, elements and/or states. Thus, such conditional language is notgenerally intended to imply that features, elements and/or states are inany way required for one or more embodiments or that one or moreembodiments necessarily include logic for deciding, with or withoutauthor input or prompting, whether these features, elements and/orstates are included or are to be performed in any particular embodiment.

While certain embodiments have been described, these embodiments havebeen presented by way of example only, and are not intended to limit thescope of the disclosure. Indeed, the novel apparatus, methods, andsystems described herein may be embodied in a variety of other forms;furthermore, various omissions, substitutions and changes in the form ofthe methods and systems described herein may be made without departingfrom the spirit of the disclosure. For example, while blocks arepresented in a given arrangement, alternative embodiments may performsimilar functionalities with different components and/or circuittopologies, and some blocks may be deleted, moved, added, subdivided,combined, and/or modified. Each of these blocks may be implemented in avariety of different ways. Any suitable combination of the elements andacts of the various embodiments described above can be combined toprovide further embodiments. The accompanying claims and theirequivalents are intended to cover such forms or modifications as wouldfall within the scope and spirit of the disclosure.

What is claimed is:
 1. A carrier aggregation system comprising: a firstsignal path including a first power amplifier associated with a firstcarrier, a first directional coupler configured to provide an indicationof power of the first carrier, and a first radio frequency switchelectrically connected to the first power amplifier by way of at leastthe first directional coupler; a second signal path including a secondpower amplifier associated with a second carrier, a second directionalcoupler configured to provide an indication of power of the secondcarrier, and a second radio frequency switch electrically connected tothe second power amplifier by way of at least the second directionalcoupler; and a frequency multiplexing circuit configured to performfrequency domain multiplexing, the frequency multiplexing circuitincluding a terminal configured to provide a carrier aggregated signal,the carrier aggregated signal including an aggregation of at least thefirst carrier and the second carrier.
 2. The carrier aggregation systemof claim 1 wherein the first radio frequency switch is a band selectswitch.
 3. The carrier aggregation system of claim 1 wherein the firstradio frequency switch is a transmit/receive switch.
 4. The carrieraggregation system of claim 1 wherein the first radio frequency signalpath includes a band pass filter, and the band pass filter is coupledbetween the first radio frequency switch and the frequency multiplexingcircuit.
 5. The carrier aggregation system of claim 4 wherein the bandpass filter is included in a duplexer.
 6. The carrier aggregation systemof claim 1 wherein the first power amplifier is a multi-mode, multi-bandpower amplifier.
 7. The carrier aggregation system of claim 1 whereinthe frequency multiplexing circuit is a diplexer.
 8. The carrieraggregation system of claim 1 wherein the carrier aggregated signal is afrequency division duplexing carrier aggregated signal.
 9. The carrieraggregation system of claim 1 wherein the first directional coupler isconfigurable such that (i) the indication of power of the first carrieris an indication of forward power in a first state and (ii) theindication of power of the first carrier is an indication of reversepower in a second state.
 10. A carrier aggregation system comprising: afirst signal path including a first power amplifier associated with afirst carrier, a first radio frequency switch, and a first directionalcoupler configured to provide an indication of power of the firstcarrier, the first directional coupler electrically connected to thefirst power amplifier by way of at least the first radio frequencyswitch; a second signal path including a second power amplifierassociated with a second carrier, a second radio frequency switch, and asecond directional coupler configured to provide an indication of powerof the second carrier, the second directional coupler electricallyconnected to the second power amplifier by way of at least the secondradio frequency switch; and a frequency multiplexing circuit configuredto perform frequency domain multiplexing, the frequency multiplexingcircuit including a terminal configured to provide a carrier aggregatedsignal, the carrier aggregated signal including an aggregation of atleast the first carrier and the second carrier.
 11. The carrieraggregation system of claim 10 wherein the first radio frequency switchis a band select switch.
 12. The carrier aggregation system of claim 10wherein the first radio frequency signal path includes a band passfilter, and the band pass filter is coupled between the firstdirectional coupler and the frequency multiplexing circuit.
 13. Thecarrier aggregation system of claim 10 wherein the first directionalcoupler is configurable such that the indication of power of the firstcarrier is an indication of forward power in one state and theindication of power of the first carrier is an indication of reversepower in another state.
 14. The carrier aggregation system of claim 10further comprising a select switch and a power detector, the powerdetector configured to receive the indication of power of the firstcarrier from the first directional coupler by way of at least the selectswitch, and the power detector configured to receive the indication ofpower of the second carrier from the second directional coupler by wayof at least the select switch.
 15. A carrier aggregation systemcomprising: a first signal path including first power amplifierassociated with a first carrier; a second signal path including a secondpower amplifier associated with a second carrier; a directional coupler;and an antenna switch configured to selectively electrically connect thefirst signal path and the second signal path to the directional coupler,the antenna switch configured to provide a carrier aggregated signal,the carrier aggregated signal including an aggregation of at least thefirst carrier and the second carrier.
 16. The carrier aggregation systemof claim 15 wherein the directional coupler is configured to provide anindication of power of the first carrier at a first time and anindication of power of the second carrier at a second time.
 17. Thecarrier aggregation system of claim 15 wherein the carrier aggregatedsignal is a time division duplexing carrier aggregated signal.
 18. Thecarrier aggregation system of claim 15 wherein the directional coupleris configured to provide an indication of forward power in a first stateand an indication of reverse power in a second state.
 19. The carrieraggregation system of claim 15 further comprising a frequencymultiplexing circuit configured to perform frequency domainmultiplexing, the frequency multiplexing circuit electrically connectedto the directional coupler by way of at least the antenna switch. 20.The carrier aggregation system of claim 15 wherein the first signal pathfurther includes a radio frequency switch and a band pass filter.